A lewd act in which, while a man is having vaginal sex with a woman from behind (doggy-style), he inserts the wrong end of a spiked dildo into her anus, so that it sticks up like the tail of the dinosaur from whom it takes its name.

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A kilsyth slang word for someone who has lots romantic relationships in a short period of time, usually referring to a girl. It originally was used say that the person in question is like the dinosaur, but no one really remembers how it relates to the prehistoric monster.

Christie is such a stegosaurus, that's her third relationship this year.

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-MAN ONLY MOVE- A "stegosaurus" is a type of dick move, much like the batwing or the brain. To successfully do the stegosaurus, you must hair gel your pubic hairs into a mohawk. After drying, lie on your back (fully naked), and get a full on erection. In this postiion, with the mohawked pubes and boner in an upside-down postion, your cock+balls will look like a roughly detailed dinosaur

Jimmy wanted to show his friends the stegosaurus, but he didn't have any hair gel.